A térd posztoperatív rehabilitációját elősegítő eszközök kifejlesztése és klinikai kipróbálása

SHORT THESIS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY (PHD) DEVELOPMENT AND CLINICAL TRIALS OF DEVICES FOR THE POSTOPERATIVE REHABILITATION OF THE KNEE JOINT by Sándo Manó Supe iso : Zol án Cse ná ony UNIVERSITY OF DEBRECEN Doc o al School o Clinical Medicine Deb ecen, 2015 2 De elopmen and clinical ials o de ices o he pos ope a i e ehabili a ion o he knee join By Sándo Manó, MSc Supe iso : Zol án Cse ná ony, MD, PhD, DSc Doc o al School o Clinical Medicine, Uni e si y o Deb ecen Head o he Examina ion Commi ee: And ás Be a, MD, PhD, DSc Membe s o he Examina ion Commi ee: Zsol Bacsó, MD, PhD Csaba Fa kas, MD, PhD The Examina ion akes place a Depa men o Oph halmology, Facul y o Medicine, Uni- e si y o Deb ecen, 04.02.2016, 11:00 Head o he De ense Commi ee: And ás Be a, MD, PhD, DSc Re iewe s: Ri a Kiss, PhD, DSc Lajos Bo bás, PhD Membe s o he De ense Commi ee: Ri a Kiss, PhD, DSc Lajos Bo bás, PhD The PhD De ense akes place a he Lec u e Hall o Bldg. A, Depa men o In e nal Medi- cine, Facul y o Medicine, Uni e si y o Deb ecen, 04.02.2016, 13:00 3 1. INTRODUCTION The numbe o di e en su gical echniques o he ea men o knee join inju ies is g owing con inuously. In cases o se ious inju ies o wea -and- ea o he join he only solu ion is he o al join eplacemen , he so called o al endop os hesis. To al join eplacemen su ge y became a ou ine in e en ion in he 1960s a i s o he hip join , hen o he knee join a li le mo e han 10 yea s la e . Acco ding o he cu en ly accep ed p edic ions he numbe o p ima y hip p os hesis im- plan a ions is said o be inc eased by 30% un il 2030, while he numbe o knee p os hesis implan a ions may quad uple. In addi ion o he g owing numbe o join eplacemen su ge ies, pos ope a i e ehabili a ion has inc easing im- po ance, since he inal ou come o he ope a ion s ongly depends on he success- ul implemen a ion o he o me . The main goal is o achie e he bes possible ange o mo ion upon he pa ien ’s discha ge om he hospi al. While he maximal lexion o he no mal knee (app ox. 150°) is beyond each, apa om a eally ew excep ions, which is accep ed bo h by he pa ien s and he su geons as well, each- ing he ull ex ension o he join is essen ial as i s absence – he lexion con ac u e – may lead o u he p oblems. Despi e he ac ha ull ex ension is eached du - ing he su ge y, he expe ience shows he de elopmen o lexion con ac u e in an o e whelming numbe o cases du ing he pos ope a i e pe iod. Based on li e a- u e da a he incidence o ex ension de ici abo e 10° eaches 24% and 37% o women and men, espec i ely. The mos common unde lying cause o he co ec able ull ex ension de ici is he p o ec i e e lex muscle spasm, igge ed by pain, bu inadequa e coope a ion o he pa ien may play an addi ional ole in mos o he cases as well. A lexion con- ac u e o e en a ew deg ees may cause ai ly ad e se biomechanical changes in he knee join , since wi h ull ex ension only minimal balancing muscle ac i i y is needed om he muscles su ounding he knee, while in a semi lexion pos u e he lexo and ex enso muscles a e being o ced o wo k con inuously du ing s anding posi ion ha leads o he ea ly exhaus ion and consequen pe manen pain o he a ec ed muscles. Addi ionally, as a esul o he inc eased p essu e be ween he 4 su aces o he join , he load on he pa ello emo al join inc eases signi ican ly as well, while la e , he b oken balance o he so issues may lead o join ins abili y. Du ing he pos ope a i e ehabili a ion ollowing o al knee eplacemen , he so called Con inuous Passi e Mo ion (CPM) de ices a e used wo ldwide as an addi ion o physio he apy. Howe e , es o ing he desi ed ange o mo ion a e he ope a- ion canno be achie ed in many cases due o he because o he muscula de ence. These de ices p o ide a signi ican aid du ing he ehabili a ion pe iod, bu acco d- ing o ou e e yday expe ience in ou depa men he cons uc ion o hese de ices does no allow he ull ex ension o he knee in all o he pa ien s, hus p ese ing he s a e o lexion con ac u e. Based on wo indings o ou own, i.e. 1) he CPM de ice does no p o ide o he ull ex ension o he knee and 2) ha pe iodic ib a ional mo ion loosens he lex- ion con ac u e, we s a ed he de elopmen o a complemen a y de ice-pai a he Depa men o O hopaedic Su ge y, Uni e si y o Deb ecen, which was p o en o signi ican ly dec ease he ex en o he lexion con ac u e. The i s membe o his pai is he so called Ele a ed Heel Res (EHR), which is ac ually a milled- o-shape ha d oam o suppo he heel. In addi ion o holding he lowe ex emi y and he knee in an ele a ed posi ion, i s impo an ea u e is ha i does no allow ou wa d o a ion so i only a ec s mo emen s and knee join componen s in he sagi al plane. I s signi icance lies in he ac ha unde physiological condi ions a heal hy indi iduals hold hei lowe ex emi y in a sligh ly ou wa d o a ed posi ion while lying supine. Should we no p e en his ou wa d o a ion while ha ing he heel ele a ed and he knee in he ai , we would c ea e a si ua ion wi h a a isa ion en- dency a ec ing he knee join . The o he membe o he de ice-pai , he Heel Vib a ing De ice (HVD) was de el- oped o p o ide hy hmical ib a ion. As he i s s ep he su geons and physio- he apis s o ou depa men es ed he de ice on hemsel es and i seemed o be eally e ec i e. The subjec i e and objec i e esul s o a pilo s udy conduc ed wi h he sys em a e he addi ion o he EHR we e p omising as well. The clinical ial ended wi h a ou able esul s, as he pa ien s ound he de ice o be well- ole able 5 and hey we e keen o use i o be e e iciency. Meanwhile, he u he ad ance- men o he de ice esul ed in a bedside cons uc ion ha does no equi e placing he pa ien on a sepa a e bed, as i can be olled beside any kind o bed and ea - men may be s a ed immedia ely. Du ing he de elopmen p ocess o he EHR and he HVD and while assessing he e iciency o pos ope a i e knee ea men s, we epea edly aced he essen ial ques ion ha how he lexion/ex ension angle o he knee can be measu ed wi h ela i ely high p ecision. In o de o answe his ques ion I ca ied ou an ex ensi e se ies o measu emen s when I assessed he p ecision and he applicabili y o an X- ay image-based measu emen me hod. 6 2. OBJECTIVES The objec i es o my wo k we e as ollows: A. Measu emen s E alua ion o knee ex ension angles based on con en ional X- ay images ap- plying a new me hod and he de e mina ion o he accu acy o his new me hod. De elopmen o he mos sui able me hod o measu emen . B. De ice de elopmen De elopmen o new de ices o he p e en ion and ea men o pos ope - a i e knee lexion con ac u e. a. De elopmen o a s a ic de ice: he Ele a ed Heel Res (EHR); b. Cons uc ion o a dynamic de ice: he Heel Vib a ing De ice (HVD); c. De elopmen o he p o o ype o a combined equipmen : he Knee Mo ing De ice (KMD) C. Clinical ials Conduc ing clinical ials wi h he newly de eloped de ices, summa ising and s a is ically analysing he expe ience ob ained du ing use. 7 3. MATERIALS AND METHODS Du ing he pos ope a i e ehabili a ion ollowing o al knee eplacemen su ge y we y o achie e he bes possible lexion, bu ull ex ension is also essen ial. P ac- ically my esea ch was based on he la e c i e ion and was ealized in wo main di ec ions. 3.1. Measu emen o knee ex ension angle based on X- ay images Measu emen o he lexion-ex ension angle o he knee seems o be a simple ask, bu using he adi ional p o ac o s and goniome e s only app oxima ed esul s may be ob ained. In o de o achie e app op ia e p ecision we need o know he exac loca ion and posi ion o he bones, which de e mine he axis o he shin and he high. An e iden solu ion may be p o ided by he analysis o ou ine la e al X- ay images, bu we ha e o ace wo p oblems du ing assessmen : (1) he X- ay images ob ained acco ding o in e na ional s anda ds do no show ei he he en i e emu o he en i e ibia and (2) he X- ay image ob ained om a di ec ion o he han he ideal la e al di ec ion may esul in dis o ed measu emen o ex ension angles on he image. In o de o clea and elimina e he e ec s o he abo e men ioned ac o s, du ing he i s pa o my wo k I ca ied ou a se ies o measu emen s ha lead o he de elopmen o a p ecise me hod o he measu emen o knee ex ension angle on X- ay images. To clea and elimina e he e ec o he abo e men ioned ac o s, du ing he i s pa o my wo k I execu ed a se o measu emen s ha leaded o he de elopmen o a p ecise me hod o measu e he knee ex ension angle based on X- ay images. 3.1.1. E alua ion o he i ual and he eal la e al axes o he high and he shin Du ing ou expe imen s we examined he di e ence be ween he eal and he i - ual X- ay based axes o he high and he shin when he di ec ion o imaging de i- 8 a es om he ideal la e al di ec ion. We ook pho os o 10 cleaned and boiled e- mu s and 10 ibia- ibula pai s om la e al di ec ion and om a ±30° angle ange wi h 2° s eps using a s epping mo o o o a e he bone a ound i s longi udinal axis. Thus, we collec ed 30+1 pho os o each emu and each ibia- ibula pai . Since he e was no so issue, which would ha e in e e ed wi h he measu emen s we we e could use a simple digi al came a ins ead o X- ay. Using a ec o g aphics edi ing so wa e we d ew he ollowing geome ical elemen s on he digi al images: 1. he line be ween he cen e o he g ea e ochan e and he cen e o he epicondyles ( emo al axis) 2. he hal -line aligned o he an e io dis al con ou o he emu 3. he hal -line aligned o he an e io p oximal con ou o he ibia 4. he hal -line aligned o he pos e io p oximal con ou o he ibia 5. he line segmen be ween he head o he ibula and he la e al malleolus In o de o e alua e he p ecision a which he lines d awn on a no mal X- ay image (No. 1, No. 2 and No. 3 hal -lines) de e mine he axis o he emu and he ibia, we measu ed he angles be ween lines 1-2, 3-5 and 4-5 (angles α, β and γ, espec- i ely). (The smalle he angle he de e mina ion o he axis o he emu o he shine is mo e p ecise by he co esponding hal -line). 3.1.2. Measu emen o knee lexion angle in di e en p ojec ions While ca ying ou ou se ies o measu emen s we sough answe o he ques ion ha how he known, p e-se lexion angles become dis o ed om di e en poin o imaging. We applied he same se -up desc ibed p e iously wi h he s epping mo- o , bu his ime we used a plas ic, ull lowe ex emi y o imaging. A e p e-se - ing knee lexion angles o 6, 10, 13, 15 and 20° successi ely, we o a ed he mon- age a ound i s axis wi h s eps o 2° in a ange o ±30° and ook pho os o each s a e. On he digi al pho os aken om di e en poin s o iew we d ew he axis o he 9 emu and he ibia using he landma ks highligh ed on he plas ic bones (based on sec ion 3.1.1. No. 2 and No. 5 lines), hen we measu ed he i ual lexion angles wi h an image p ocessing so wa e on all o he images. 3.2. De elopmen o ehabili a ion de ices o he ea men o lexion con- ac u e 3.2.1. The Ele a ed Heel Res (EHR) As he i s s ep o ou de ice de elopmen sub-p ojec we de eloped he de ails o he EHR ha assis s he s a ic elaxa ion and ex ension. The EHR is a cube om ha d oam ha con ains a e ical g oo e ha suppo s and ixes he heel and he o eleg up o he la e al malleolus and assu es ha he lowe limb ele a es om he plane o he bed. As he axis o he leg is ixed in e ical posi ion, i p e en s he la e al o a ion o he hip and assu es he ho izon al posi on o he c oss axis o he knee join , so he e ec o he o ce o g a i y clea ly y o ex end he knee. The eal e iciency o he EHR could be expe ienced du ing long- ime use o pa allel applica ion o he de ice desc ibed in he nex sub-chap e . 3.2.2. The bed-dependen e sion o he Heel Vib a ing De ice (HVD) This de ice is basically a mechanical cons uc ion connec ed o an ex a-low ol - age con ol uni ha was de eloped based on he ollowing equi emen s: - he ampli ude and he equency o he ib a ion mus be con inuously adjus able (be ween 10-30 mm and 1-3 Hz, espec i ely) - he de ice mus be p og ammable - he dimensions o he de ice mus allow i o be posi ioned a he end o he pa ien bed In o de o demons a e he e iciency o hese newly de eloped EHR and HVD we conduc ed a andomized clinical ial in ol ing 144 pa ien s, who unde wen p i- ma y o al knee eplacemen su ge y. Du ing he ial we basically examined ha wha kind o ex ension esul s may be achie ed wi h ou new de ices compa ed o 16 he p e-se knee lexion angle, hus de e mining he di e ence be ween he known p e-se angle and he i ual angle econs uc ed by he cons uc ion lines d awn on he X- ay images. The impo ance o his expe imen lies in he ac ha i is essen ial o know he objec i i y and p ecision o he X- ay image-based measu e- men alues in pa ien s wi h signi ican lexion con ac u e occu ing di ec ly e en in he pos ope a i e pe iod o la e (which is some imes a ue issue in he clinical p ac ice, wha e e he unde lying cause migh be). A e p ocessing he da a we may d aw simila conclusion as in he p e iously de- sc ibed expe imen , i.e. i we conside he knee as a sys em and we examine he ull lowe ex emi y, he signi icance o de ia ion om he ideal la e al di ec ion du - ing X- ay imaging – while s aying wi hin a ela i ely no mal ange - is less han we an icipa ed. The e o in angle es ima ion in ela i ely ex eme condi ions ( lexion con ac u e o 20° wi h a de ia ion o 30° om he la e al di ec ion du ing imag- ing) was only 2.5°, which is negligible in he clinical p ac ice. Ne e heless, acco d- ing o ou expe ience, he inc ease in he lexion angle o he knee causes an expo- nen ial ele a ion o he e o in axis de e mina ion, e en wi h la e al de ia ions o 10-20° du ing imaging. Based on ou expe imen s we may conclude ha using la e al X- ay images o he measu emen o knee ex ension angles, mo e accu a e alues may be achie ed du - ing imaging wi h knee being ex ended and wi h a heel suppo in use, which also ensu es ha he opposi e knee will be ou side o he image. In hese ins ances he X- ay casse es may be posi ioned di ec ly nex o he ex emi y o be assessed, on o he bed, o on a console placed beside he bed. Using his se -up we sugges aking la e al X- ay images in o de no o miss any impo an de ails, bu a he same ime o ge he images om a ai ly impo an posi ion sui able o measu ing he ull ex ension angle. Based on ou measu emen s we concluded ha while he accu acy o o he knee angle measu emen me hods a e ques ionable ega ding he measu emen aken 17 in ull ex ension, la e al X- ay images aken in ully ex ended posi ion p o ide ac- cu a e and eliable measu emen esul s. I should be no ed ha ou measu emen me hod can be applied o knees wi h no mal ana omy only, hus his p ocedu e may no be sui able in ce ain cases (nea knee ac u es, os eo omies, exos oses). 5.2. De elopmen o ehabili a ion de ices o he ea men o lexion con- ac u e The ‘gold-s anda d’ in he pos ope a i e ehabili a ion o o al knee eplacemen has been he CPM ea men o decades. The a ou able e ec o he sys em on knee lexion was examined and demons a ed in se e al publica ions, bu i s e ec on ex ension is ques ionable a leas , p edominan ly because – acco ding o ou own expe ience as well – he ex ension angle se on he de ice is a o om he eal ex ension angle. Ou p ima y objec i e was o de elop a de ice ha can be applied in he ea ly pos - ope a i e ehabili a ion pe iod a e p ima y o al knee eplacemen su ge y. Ap- plying a ib a ing mo ion o he heel ( ela i ely apid and hy hmic upwa ds and downwa ds mo ing i.e. ib a ion), he ine ial o ces in addi ion o he mass o he ull lowe ex emi y help he ex ension o he knee and he elaxa ion/ex ension o he pos e io so issues, he eby p e en ing he de elopmen o an ex ension de - ici . Applying his de ice concomi an ly wi h a CMP machine p o ides he neces- sa y e ec o knee lexion as well. The i s phase o he de elopmen p ocess esul ed in he cons uc ion o he i s , bed-dependen e sion o he Heel Vib a ion De ice. The wo king p inciple o he de ice is ha he machine o ce he heel o he a ec ed lowe ex emi y o ib a e wi h an adjus able ampli ude and equency, while he pa ella and he ans e se axis o he knee emain ho izon al. This way, he ine ia and he mass o he lowe ex emi y exe a passi e ex ension e ec a he bo om end-poin o he mo emen on he pos e io s uc u es o he knee join , which in u n helps i o each he ulles ex ension possible. 18 A e elimina ing he p oblems and he ‘unease-o -use’ o he i s e sion, we de- eloped a new, bedside, olling, hus much mo e mobile design o he HVD ha can be easily posi ioned. In his cons uc ion he heel o he pa ien is placed in a bel ha p o ides a ce ain le el o sel -adjus men o he ope a ed lowe ex emi y du ing he apy, since i se s he ma gins o he oo in e ical posi ion. The de ice can be con olled e y easily, e en by he pa ien , u he mo e, he ea men does no ha e any special equi emen s, as i can be ca ied ou on any egula hospi al bed. A e s a ing he de ice, he ea men does no equi e supe ision by he physio he apis , he e o e, in addi ion o i s ou s anding e iciency he de ice sa es signi ican human esou ces as well. Conside ing he ac ha we achie ed ai ly eliable esul s wi h e y sho -du a ion ea men s, la e on we plan o ex end he du a ion o he ea men s and exploi he e iciency o he de ice e en mo e. Ac- co ding o ou expe ience, pa ien s ole a e he ea men o a du a ion o 10 minu es, bu as soon as we ha e mo e o hese de ices, we s ongly ecommend o epea he ea men mo e imes pe day. Randomized p ospec i e clinical ials we e conduc ed o he e alua ion o he e - iciency o bo h de ices. The ial esul s wi h he o iginal HVD demons a ed ha he numbe o pa ien s in he sa is ac o y ex ension ca ego y o 0°± 5° was highe by 25% in he g oup ea ed wi h HVD compa ed o he con ol g oup ea ed wi h CPM only. The cu en ly on-going clinical ial wi h he imp o ed, bedside e sion o he HVD has a sligh ly e ised p o ocol o he be e de ec ion o he e ec o he de ice on he lexion con ac u e. Acco dingly, he analysis ocused on he da a o pa ien s wi h p e-exis ing lexion con ac u e. The esul s demons a ed ha he ex en o lexion con ac u e imp o emen was much highe among pa ien s using he HVD compa ed o he g oup o pa ien s, who we e ea ed wi h CPM only (imp o emen o 2.4° s -0.9°). Co esponding o he gene al p ac ice in Hunga y we did no employ any knee sco e sys ems du ing he e alua ion o ou esul s. De ailed case his o ies we e 19 aken and ho ough physical examina ions we e ca ied ou be o e su ge y, u - he mo e we used isual analogue scale o he be e assessmen o he subjec i e aspec s o ou esul s. The e we e no complica ions a all du ing he clinical applica ion o he de ice and he pa ien s ole a ed he ea men excep ionally well and he e was no single case whe e he discon inua ion o he 7-day long ea men became necessa y on he pa ien ’s eques . Some imes he pa ien s did no wan o use he de ice o he ull 10 minu es du ing he i s he apeu ic session, bu he necessa y ole ance was eached a he nex o a he hi d session a he la es . The applica ion o he HVD is on-going wi hin he amewo k o he clinical ial and in he clinical p ac ice as well, bu no acco ding o he assignmen de e mined du ing andomiza ion. We use i p ima ily in di icul cases a e o al knee eplace- men and o pa ien s who a e suscep ible o he de elopmen o lexion con ac- u e due o hei p eope a i e de o mi y o ex ension de ici o e en due o an ab- no mal gai o pos u e. In summa y, we may conclude ha we success ully de eloped and in oduced a de ice o clinical p ac ice, which can be applied o he p e en ion and ea men o pos ope a i e lexion con ac u es du ing he ea ly pos ope a i e pe iod wi h p omising esul s, p ima ily in cases o o al knee eplacemen , bu i can be used in condi ions wi h simila ly dec eased anges o mo ion bu wi h a iable unde ly- ing cause. The applica ion o ou HVD and EHR du ing he pos ope a i e ehabili a ion pe iod was p o en o signi ican ly dec ease he occu ence o lexion con ac u es, so he con inuous applica ion o hese de ices is easonable and s ongly ecommended. The esul s o ou de elopmen we e published in pee - e iewed jou nals in o de o main ain ou ole as he p op ie o s o his in en ion. A e he de elopmen o he bedside HVD a easonable need was conside ed, namely o me ge he ad an ages o he CPM and he HVD in a single de ice. In o de o accomplish his challenge we s a ed o cons uc a new de ice (Knee Mo ing 20 De ice, KMD), which cu en ly is in he inal s age o de elopmen . The compu e - con olled KMD is able o mo e he knee in i s ull ange o mo ion acco ding o he ins alled ea men p og ams and is capable o applying he ib a ing unc ion o he HVD a angled posi ions and in ull ex ension as well. Acco ding o ou plans he inal e sion would include a o ce measu emen sys em buil in o he heel sup- po , which would p o ide eedback o he sys em and he e o e would allow a new, o ce-based con ol mode as well, so he a ge alue o he mo ing could be a o ce ins ead o an angle o e en he combina ion o hese. Thus, o example we may se a o ce limi o he ex ension mo ing, bu he angle posi ion o he ex en- sion would be di e en ea men -by- ea men o e en in each mo ing cycle. 21 6. SUMMARY The issue o knee lexion con ac u e a e o al knee eplacemen su ge y appea s o occu ela i ely o en. I may cause p oblems in one- hi d o qua e o he pa- ien s, and may ei he mani es as a limi a ion o he ROM o as an inc eased load o he su ounding muscles and he join su aces. In he i s pa o my wo k I ocused on he measu emen o lexion con ac u e. I ied o ind a eliable measu emen me hod ha can be used o p ecisely de e - mine he angle o he con ac u e and he ex ension. The esul s demons a ed ha an X- ay image-based angle measu emen p o ides high accu acy e en wi h sho ilms and e en when he di ec ion o he X- ay imaging is no exac ly la e al. A e analysing he measu emen me hod o he knee lexion-ex ension angle, a new de ice has been de eloped du ing second pa o my wo k – he Heel Vib a ing De ice – o he ea men o lexion con ac u e. This de ice signi ican ly and e - ec i ely dec eases he angle and he incidence o lexion con ac u es as an addi- ion o he CPM compa ed o he CPM used alone. The esul s o he clinical ial wi h he i s e sion o he de ice in ol ing 144 pa ien s we e a ou able and he u he ad anced design p o ed o be e en mo e p omising. The pa ial esul s om he cu en ly on-going clinical ial show ha he applica ion o he de ice leads o signi ican imp o emen s in he p e en ion and he ea men o lexion con ac u e (p=0.0033) compa ed o a con en ional CPM de ice. The esul s o he o e all wo k consis o an angle measu emen me hod based on X- ay images, de eloped o he accu a e de e mina ion o knee ex ension angle and suppo ed by se e al hund ed measu emen s, u he mo e, a ehabili a ion de ice ha can be applied e ec i ely o he p e en ion and ea men o lexion con ac u e as i was demons a ed in clinical ials. 22 7. NEW RESULTS A. Measu emen s a. Using a new me hod de eloped by me and using con en ional la e al X- ay images I de e mined i. he axis o he emu is p ac ically pa allel wi h he an e io co ical; ii. he pos e io co ical o ibia is he mos sui able line o he de e - mina ion o he axis o he shin. b. I p o ed ha du ing he e alua ion o he lexion-ex ension angle o he knee, he dis o ion e ec o he la e al de ia ion o imaging is minimal: wi hin he ealis ic ±30° ange i is bellow 2.5°. B. De ice de elopmen a) We de eloped a ela i ely simple s a ic aid o he suppo o he heel, called he Ele a ed Heel Res , which was applied as a eally use ul accesso y bo h du ing he pos ope a i e ehabili a ion and du ing ob aining he la e al X- ay images as well. b) We de eloped an o iginal hen an ad anced e sion o a de ice, called he Heel Vib a ing De ice o he p e en ion and ea men o pos ope a i e knee lexion con ac u es. c) We cons uc ed he p o o ype o an ins umen ( he Knee Mo ing De ice) ha combines he mo ing unc ions o he cu en CPM de ices and he new ib a ing unc ion o he HVD as well. We an icipa e u he e iciency im- p o emen om his de ice compa ed o he HVD bu i s clinical in oduc- ion will ake place in 2016. C. Clinical ials We conduc ed clinical ials wi h he newly de eloped HVD and EHR p o o ypes ha demons a ed he e iciency o he de ices. Based on he esul s we demon- s a ed ha he applica ion o bo h e sion o he HVD in addi ion o he EHR leads o signi ican ly mo e a ou able esul s compa ed o he CPM in dec easing knee ex ension de ici s. 23 ACKNOWLEDGEMENTS In he i s place, I hea ily hank my supe iso , P o esso Zol án Cse ná ony o his highly p o essional and humane suppo . Wi h his ex ended p o essional expe- ience, use ul pieces o ad ice and con inuous encou agemen he signi ican ly con- ibu ed he o ganiza ion and he execu ion o he measu emen s and he conduc- ion o he clinical ials, u he mo e, he p o ided in aluable help du ing he p o- cessing and he analysis o he esul s. He was my main suppo in my o ien a ion as an enginee in a clinical en i onmen . I would like o hank o he suppo and he use ul pieces o ad ice I go om Judi Pálinkás and János Szabó a he beginning o he clinical ials. Special hanks o he physio he apis o ou depa men Ka alin Bakó, Ve onika Kósa, Lí ia Ta and Ágnes Bagi and u he mo e o Zol án Fehé . I would like o hank Gyula Győ i, who con ibu ed o he compila ion o he he- ses, u he mo e, hanks o he ollowing pe sons o hei help du ing he de el- opmen p ocess o he de ices and in he edi ing o he publica ions: Is án Szabó, Ka alin Deu sch, Tibo Juhász, Judi T. Nagy, Pé e Zsoldos, László Kiss. And in he end, and mos impo an ly, I would like o hank my wi e Mónika and my child en Sanci and Majácska o hei suppo and long-las ing pa ience. 24 25